According to the Center of Volcanology and Geological Hazard Mitigation (CVGHM), Lamongan has not erupted since 1898. On several occasions since then, however, seismic activity has increased. Brief periods of earthquakes and earthquake swarms occurred in 1924-25, 1978, 1985, and 1988 (SEAN 10:10, 10:11, 13:02). The Darwin Volcanic Ash Advisory Centre (VAAC) reported on 24 September 2003 that aircraft personnel had observed ash over the volcano to a height of about 900 m, but this was not confirmed by on-scene observers (BGVN 28:12). Our previous report noted continuous tremor and an earthquake swarm on 5-6 January 2005 (BGVN 31:01).

CVGHM reported that during 1 February-9 March 2012, diffuse white plumes rose at most 20 m above Lamongan's crater. Seismicity increased on 23 February, then fluctuated in intensity through 7 March. Seismicity increased significantly on 8-9 March (table 1). CVGHM raised the Alert Level to 2 (on a scale of 1-4) on 9 March, and began to monitor the volcano more intensively. Residents and tourists were prohibited from going within a 1-km-radius of the active crater. No eruptions occurred during the reporting period. Increased seismic activity at Lamongan continued at least through 12 March.

Table 1. Seismicity at Lamongan during 1 January-9 March 2012. Data from CVGHM. Shallow volcanic earthquakes were not reported and categories were not defined in the reports.

CVGHM reported that during 1 February-9 March diffuse white plumes rose at most 20 m above Lamongan. Seismicity increased on 23 February, then fluctuated in intensity through 7 March. Seismicity increased significantly on 8 March and tremor was recorded continuously the next day. CVGHM raised the Alert Level to 2 (on a scale of 1-4) on 9 March. Residents and tourists were prohibited from going within a 1-km-radius of the active crater.

Information is preliminary and subject to change. All times are local (unless otherwise noted)

"Lamongan experienced a seismic swarm with ground breakage 2-15 October. More than 3,000 earthquakes were recorded at the VSI observation post at Gunungmeja, near Klakah, W of Lamongan (figure 1). Two additional seismometers were installed in the epicentral area on 5-6 October. Ground breakage occurred in a region ~5 km W of the summit and consisting of numerous ground cracks, some with vertical offsets of 15 cm, striking ENE. No changes were noted in the temperatures or character of the many lakes in the Lamongan area, which fill maars created by prehistoric eruptions. The 1985 activity is in the same general area as two seismic swarms that occurred in 1924-25 and in 1978 but did not culminate in eruptions."

Figure 1. Map of Lamongan, after Van Bemmelen, 1949. Contour interval is 250 m. Contours on the W side of the map mark the lower E flank of Tengger Caldera. Fissures shown are from the 1924-25 earthquake swarm.

"Lamongan was quite active during the 19th century with 40 eruptions, including more than a dozen that produced lava flows. Most were from vents located on the W flank above about 400 m altitude. It is notable that the maars on the W slope of Lamongan all occur at elevations below the historic eruption vents, suggesting that the position of the groundwater table controls its eruptive style. Eruptions from above 400 m altitude form fissure vents and cinder cones that pose little threat to the local inhabitants. Activity from vents below 400 m may give rise to explosive, maar-forming eruptions. The 1985 epicentral area has a surface elevation of 200-380 m. Plans are underway to increase the level of surveillance."

"November activity consisted of an average of one earthquake/day in the October swarm area W of the volcano. Detailed geological and monitoring efforts are now in progress by VSI to evaluate the possibility of a future eruption from the epicentral area."

A brief seismic swarm centered immediately W of Lamongan cone began on 8 February at 0445. Additional seismicity was recorded through February. No changes have been noted in the temperature or behavior of the maar lakes within the epicentral region. The earthquakes occurred in virtually the same epicentral area as those from the 1978 and 1985 swarms.

In this 2003 case, no confirmations of a plume or other signs of volcanism were available from observers on the scene. Concrete confirmations can establish that the plume did indeed vent here, rather than at another volcano and that it did not result from similar-looking processes of non-volcanic origin (eg., forest fires, crop burning, lofted dust).

Elevated seismicity occurred at Lamongan on 5-6 January 2005. From 1200 to 0700 on 5 January, 22 events occurred with Modified Mercali Intensity (MMI) of 1. At each of three times (0331, 0447, and 0524) observers noted an event of MMI 3. During this period, instruments detected continuous tremor with an amplitude of 3 to 15 mm. On 5 January there were 282 local tectonic earthquakes and 53 volcanic A-type earthquakes. The volcano alert level was raised to 2.

On 6 January 2005, 107 volcanic A-type earthquakes were recorded. Local tectonic earthquakes over the two day period occurred 159 times, of which 10 of them were events had Modified Mercali Intensity (MMI) of 1-3.

According to the Center of Volcanology and Geological Hazard Mitigation (CVGHM), Lamongan has not erupted since 1898. On several occasions since then, however, seismic activity has increased. Brief periods of earthquakes and earthquake swarms occurred in 1924-25, 1978, 1985, and 1988 (SEAN 10:10, 10:11, 13:02). The Darwin Volcanic Ash Advisory Centre (VAAC) reported on 24 September 2003 that aircraft personnel had observed ash over the volcano to a height of about 900 m, but this was not confirmed by on-scene observers (BGVN 28:12). Our previous report noted continuous tremor and an earthquake swarm on 5-6 January 2005 (BGVN 31:01).

CVGHM reported that during 1 February-9 March 2012, diffuse white plumes rose at most 20 m above Lamongan's crater. Seismicity increased on 23 February, then fluctuated in intensity through 7 March. Seismicity increased significantly on 8-9 March (table 1). CVGHM raised the Alert Level to 2 (on a scale of 1-4) on 9 March, and began to monitor the volcano more intensively. Residents and tourists were prohibited from going within a 1-km-radius of the active crater. No eruptions occurred during the reporting period. Increased seismic activity at Lamongan continued at least through 12 March.

Table 1. Seismicity at Lamongan during 1 January-9 March 2012. Data from CVGHM. Shallow volcanic earthquakes were not reported and categories were not defined in the reports.

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.

Volcano Types

Rock Types

Tectonic Setting

Subduction zoneContinental crust (> 25 km)

Population

Within 5 kmWithin 10 kmWithin 30 kmWithin 100 km

6,588
66,387
2,193,829
15,322,387

Geological Summary

Lamongan, a small stratovolcano located between the massive Tengger and Iyang-Argapura volcanic complexes, is surrounded by numerous maars and cinder cones. The currently active cone has been constructed 650 m SW of Gunung Tarub, the volcano's high point. As many as 27 maars with diameters from 150 to 700 m, some containing crater lakes, surround the volcano, along with about 60 cinder cones and spatter cones. Lake-filled maars, including Ranu Pakis, Ranu Klakah, and Ranu Bedali, are located on the E and W flanks; dry maars are predominately located on the N flanks. None of the maars has erupted during historical time, although several of the youthful maars cut drainage channels from Gunung Tarub. The volcano was very active from the time of its first historical eruption in 1799 through the end of the 19th century, producing frequent explosive eruptions and lava flows from vents on the western side ranging from the summit to about 450 m elevation.

References

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography.

Emission History

There is no Emissions History data available for Lamongan.

Photo Gallery

Lamongan, a small volcano located between the massive Tengger and Iyang-Argapura volcanoes, rises above Lamongan Lake on its western flank. Ranu Lamongan lake fills one of 27 maars that surround the volcano, that have diameters ranging from 150 to 700 m. There have been frequent explosive eruptions, mostly from the summit crater, during the 19th century.

Photo by Tom Casadevall, 1985 (U.S. Geological Survey).

The Gunung Anyar scoria cones were formed during an eruption in 1898 at 400 m elevation on the SW flank of Lamongan. The eruption began on 5 February. Activity slowed by the 7th, but the emission of two small lava flows continued, the largest of which traveled 300 m by the time it stopped on 15 February.

Photo by Tom Casadevall, 1987 (U.S. Geological Survey).

A view of Lamongan volcano from the west shows the forested summit of Gunung Tarub, forming the highest point on the volcano to the left, with a younger, sparsely vegetated cone (Gunung Lamongan) constructed to the SW. A volcanic spine was located in the summit crater, which has been the source of most historical eruptions.

This lake-filled maar on the NE flank of Lamongan is one of 27 surrounding the volcano. Most historical eruptions have originated from the summit crater.

Photo by Tom Casadevall, 1987(U.S. Geological Survey).

Lamongan volcano is located between the Tengger and Iyang-Argapura volcanic complexes. A cluster of 27 maars, many filled by lakes, and 37 scoria cones surround the volcano. Tarub is the volcano's highest peak to the left. Lamongan was frequently active during the 19th century, producing both explosive eruptions and lava flows.

Photo by Tom Casadevall, 1985 (U.S. Geological Survey).

Lamongan volcano is located between the Tengger and Iyang-Argapura volcanic complexes. A cluster of 27 maars, many filled by lakes, and 37 scoria cones surround the volcano. Tarub is the volcano's highest peak to the left. Lamongan was frequently active during the 19th century, producing both explosive eruptions and lava flows.

Photo by Tom Casadevall, 1987 (U.S. Geological Survey).

The sparsely vegetated slopes of Gunung Lamongan rise above grasslands at the western flank of the volcano.

Photo by Sumarma Hamidi, 1973 (Volcanological Survey of Indonesia).

The small Lurus volcanic complex (middle right) lies along the northern coast of eastern Java, below and to the right of the low clouds at the right-center. Lurus lies N of the Iyang-Argapura massif, the broad volcanic complex covering much of the left center of this aerial view from the NE. The conical volcano beyond Iyang-Argapura is Lamongan volcano, and the Tengger-Semeru massif lies along the center of the horizon. The triple-peaked volcano on the right horizon is Kawi-Butak.

Photo by Lee Siebert, 2000 (Smithsonian Institution)

GVP Map Holdings

The maps shown below have been scanned from the GVP map archives and include the volcano on this page. Clicking on the small images will load the full 300 dpi map. Very small-scale maps (such as world maps) are not included. The maps database originated over 30 years ago, but was only recently updated and connected to our main database. We welcome users to tell us if they see incorrect information or other problems with the maps; please use the Contact GVP link at the bottom of the page to send us email.

Smithsonian Sample Collections Database

External Sites

Middle InfraRed Observation of Volcanic Activity (MIROVA) is a near real time volcanic hot-spot detection system based on the analysis of MODIS (Moderate Resolution Imaging Spectroradiometer) data. In particular, MIROVA uses the Middle InfraRed Radiation (MIR), measured over target volcanoes, in order to detect, locate and measure the heat radiation sourced from volcanic activity.

Using infrared satellite Moderate Resolution Imaging Spectroradiometer (MODIS) data, scientists at the Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, developed an automated system called MODVOLC to map thermal hot-spots in near real time. For each MODIS image, the algorithm automatically scans each 1 km pixel within it to check for high-temperature hot-spots. When one is found the date, time, location, and intensity are recorded. MODIS looks at every square km of the Earth every 48 hours, once during the day and once during the night, and the presence of two MODIS sensors in space allows at least four hot-spot observations every two days. Each day updated global maps are compiled to display the locations of all hot spots detected in the previous 24 hours. There is a drop-down list with volcano names which allow users to 'zoom-in' and examine the distribution of hot-spots at a variety of spatial scales.

The Sentinel Hub Playground provides a quick look at any Sentinel-2 image in any combination of the bands and enhanced with image effects; Landsat 8, DEM and MODIS are also available. Sentinel Hub is an engine for processing of petabytes of satellite data. It is opening the doors for machine learning and helping hundreds of application developers worldwide. It makes Sentinel, Landsat, and other Earth observation imagery easily accessible for browsing, visualization and analysis. Sentinel Hub is operated by Sinergise

Incorporated Research Institutions for Seismology (IRIS) Data Services map showing the location of seismic stations from all available networks (permanent or temporary) within a radius of 0.18° (about 20 km at mid-latitudes) from the given location of Lamongan. Users can customize a variety of filters and options in the left panel. Note that if there are no stations are known the map will default to show the entire world with a "No data matched request" error notice.

Geodetic Data Services map from UNAVCO showing the location of GPS/GNSS stations from all available networks (permanent or temporary) within a radius of 20 km from the given location of Lamongan. Users can customize the data search based on station or network names, location, and time window. Requires Adobe Flash Player.

The DECADE portal, still in the developmental stage, serves as an example of the proposed interoperability between The Smithsonian Institution's Global Volcanism Program, the Mapping Gas Emissions (MaGa) Database, and the EarthChem Geochemical Portal. The Deep Earth Carbon Degassing (DECADE) initiative seeks to use new and established technologies to determine accurate global fluxes of volcanic CO2 to the atmosphere, but installing CO2 monitoring networks on 20 of the world's 150 most actively degassing volcanoes. The group uses related laboratory-based studies (direct gas sampling and analysis, melt inclusions) to provide new data for direct degassing of deep earth carbon to the atmosphere.

WOVOdat is a database of volcanic unrest; instrumentally and visually recorded changes in seismicity, ground deformation, gas emission, and other parameters from their normal baselines. It is sponsored by the World Organization of Volcano Observatories (WOVO) and presently hosted at the Earth Observatory of Singapore.

EarthChem develops and maintains databases, software, and services that support the preservation, discovery, access and analysis of geochemical data, and facilitate their integration with the broad array of other available earth science parameters. EarthChem is operated by a joint team of disciplinary scientists, data scientists, data managers and information technology developers who are part of the NSF-funded data facility Integrated Earth Data Applications (IEDA). IEDA is a collaborative effort of EarthChem and the Marine Geoscience Data System (MGDS).